General Installation Sequence
Information
- For vehicles with refrigerant R1234yf, only SP-A2 refrigerant oil can be used.
- For vehicles with refrigerant R134a, only SP-A2 refrigerant oil can be used.
Information
Information for vehicles with refrigerant R1234yf:
- Every time the air conditioning servicing equipment for R1234yf is switched on, an internal test is performed on the air conditioning servicing equipment. This takes a certain amount of time. We recommend therefore that you switch on the air conditioning servicing equipment every morning before starting work, irrespective of the work order.
After connecting the air conditioning servicing equipment to the refrigerant circuit on the vehicle, a gas analysis is performed first with the following results:
- The analysed refrigerant R1234yf complies with specifications - the planned work can be performed using the air conditioning servicing equipment.
- An error occurred during the gas analysis - the fault must be determined and corrected and the gas analysis must then be repeated.
- The analysed refrigerant R1234yf does not comply with specifications - the analysed refrigerant must be extracted as refrigerant of unknown composition and must be returned to your gas supplier for treatment (or disposal), for example (see section "Filling contaminated refrigerant into a recycling bottle for analysis, treatment (or disposal)").
- The refrigerant used must be of a certain purity for the air conditioning servicing equipment to operate.
- Contamination from other refrigerants or gases can result in damage and can cause the air-conditioning system to stop working.
- Contaminated refrigerant must be returned to your gas supplier as gas of an unknown composition in accordance with legal requirements for treatment (or disposal), for example.
- To ensure that liquid parts (e.g. drops of refrigerant oil) in the extracted refrigerant gas do not falsify the result of the gas analysis, the gas analysis equipment is fitted with separators (filters) that separate these liquid droplets. Replace the filters in accordance with the specifications provided in the operating instructions for the gas analysis equipment or air conditioning servicing equipment.
Charging valves are located on the left in the engine compartment and some are under the trim panel.
> WM, 700219 REMOVING AND REINSTALLING FRONT TRIM PANEL (ENGINE COMPARTMENT)
Information
- The ignition must be off on hybrid vehicles. This ensures that the shut-off valve for the high-voltage battery refrigerant circuit is open.
- Hybrid only: Switch off ignition. The shut-off valve for the high-voltage battery refrigerant circuit is then open.
- Screw off protection caps on the charging valves.
Protection caps on charging valves
Before connecting the high-pressure and low-pressure lines to the vehicle, remove any refrigerant remaining in the lines by suction.
Service connection
- Connect the high-pressure and low-pressure lines on the air conditioner.
Information
- On air-conditioning service equipment with a transparent oil separator, read off and take note of the oil level before removing refrigerant.
- Do not carry out this step on empty air-conditioning systems (pressure gauge approx. 0 bar) because if you do, air will get into the refrigerant bottle.
- If the vehicle is cold, it may be necessary to repeat the suction procedure until all refrigerant has been removed from the air-conditioning system. This step is carried out automatically with some units.
- 3.1
- 3.2 Leave the engine running for a short time with the air conditioning on, then connect the high-pressure and low-pressure lines of the air conditioner.
- 3.3 Open the valves of the high-pressure and low-pressure lines.
Information
- Instructions in the operating instructions for the air-conditioning servicing equipment take precedence. The procedure described here may differ from the description provided by the respective air-conditioning servicing equipment manufacturer.
- Remove refrigerant by suction.
- Carry out repairs.
- 5.1 The open air-conditioning system must not be left open unnecessarily, but must be closed off using suitable stoppers immediately after being opened.
Information
The desiccator must be replaced in the following situations:
- Refrigerant circuit is open for > 20 minutes.
- Amount of refrigerant extracted is < 30% of the required quantity.
- Refrigerant circuit has been open for an indefinite period of time (gradual leak, stone damage to condenser).
- Air-conditioning compressor has become blocked.
- Dryer cartridge is damaged.
- After opening the packaging and line connections (on a new desiccator), the desiccator must be installed within 20 minutes at the latest and the refrigerant circuit must be closed, evacuated and filled.
The desiccator must not be replaced in the following situations:
- If the components are closed off using stoppers immediately after opening the refrigerant circuit or if the refrigerant circuit is closed and evacuated within 20 minutes at the latest.
- 5.2 Before closing off the refrigerant circuit, check whether the desiccator needs to be replaced.
- 5.3 Re-connect high-pressure and low-pressure lines if necessary.
- 5.1 The open air-conditioning system must not be left open unnecessarily, but must be closed off using suitable stoppers immediately after being opened.
- Evacuate the system and check for leaks.
- 6.1 If the air-conditioning system has been opened, evacuation should last at least 20 minutes so that the moisture can evaporate and be removed by suction.
- Fill the air-conditioning system.
- 7.1 Fill in the required amount of refrigerant in accordance with the specifications in the Technical data or on the sticker using the air conditioning servicing equipment for R1234yf.
> 8X00IN Technical data for air-conditioning system with R1234yf and R134a
NOTE: Excessively high pressure in refrigerant circuit- Risk of damage to air-conditioning compressor
→ Do not allow low-pressure gauge to go above 3 bar.
- Risk of damage to air-conditioning compressor
- 7.2
- 7.1 Fill in the required amount of refrigerant in accordance with the specifications in the Technical data or on the sticker using the air conditioning servicing equipment for R1234yf.
- Add refrigerant from both connection hoses to the air-conditioning system in the vehicle.
- 8.1 The refrigerant in the high-pressure and low-pressure lines is part of the filling capacity of the refrigerant in the air-conditioning system in the vehicle.
- 8.2 Close the valve on the high-pressure line and disconnect it from the vehicle.
- 8.3 Start the engine and air-conditioning system. When the pressure on both pressure gauges falls below 2 bar, close the valve on the low-pressure line and disconnect it from the vehicle.
Information
- After filling the air-conditioning system, the valve on the high-pressure and low-pressure connection must be checked using a leak detector.
- The protection caps must not be fitted.
- Position the leak detector at a specified distance (see operating instructions for each leak detector) above the valves and check the valves for signs of any leaks.
- Check the high-pressure and low-pressure connections for leaks using a leak detector.
- If there are no leaks in the high-pressure and low-pressure connection valves, fit the caps.
- Check cooling output.